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All Plugs Oil Fouled - looking for suggestions

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BRAVOZULU9 Christian Ballester
Alexandria, VA, USA   USA
Good morning Gentlemen (and a few others),

When pulling plugs yesterday in an effort to narrow some rough idling conditions, I noticed all six plugs are fouled with oil. I'm looking for some targeted suggestions on how to address this. I'll attach some photos here but I wanted to provide some context:

1-When I bought the car recently, it was idling at about 1500-1800 RPM both cold (with choke knob pushed in) and warm after running for over an hour. Therefore, I fellow forum member here locally helped me adjust timing as it was off. Now, that adjustment brought the idle almost to a shutter (about 600-800 RPM).

2-I plugged the vacuum line going from the distributor to the carb (retard, I believe); this brought my idle back to ~1000 but still a little rough; some surge but very slight.

3-Compression test. Full disclosure-this is the first time I've done this on any car and I used a brand new but low-quality tester (Harbor Freight). I followed the following procedure:

a-Car was warm but not hot; was sitting for about 1 hour after driving before I removed plugs and began testing.
b-Removed each plug; removed the ignition coil cable; crimped the fuel line between fuel filter and pump
c-Began w/ #1 cylinder - while pressing fully down on accelerator pedal, I cranked for 6-9 seconds while watching the gauge through the windshield.

Each time I cranked, the gauge needle moved progressively upward (for the most part) and largest movements were in the first couple of cranks.

The recorded numbers are below in the photo below each plug.

My question:

Each plug is fouled. Most of what I've been able to find online addressing single plugs being oil-fouled; not all of them. Any ideas here folks?

Additional Context: 3 years ago and ~600 miles ago the engine was 'rebuilt' by a British Car shop in San Luis, Obispo CA. I called that shop yesterday and they quickly verified that yes, the work was done. SO, in your suggestions please consider assuming the rebuild was quality. I think it's probable easier to just say 'the rebuild is crap', and that is certainly a possibility. However, what I'm looking for are suggestions as to what ELSE may be causing this so that I can incrementally troubleshoot instead of going straight to removing the head.

Initial Thoughts on My Part: Is is possible that somehow crankcase venting is not occurring properly?

Thanks very much everyone!

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Attachments:
Removed Plug Set.jpeg    36.9 KB
Removed Plug Set.jpeg

trtyme Avatar
trtyme T Tyme
Buford, WY, USA   USA
Maybe it is running VERY rich?

BRAVOZULU9 Christian Ballester
Alexandria, VA, USA   USA
Would that explain oil vs fuel on the plugs? (Please forgive my ignorance).

Also, I failed to mention that the exhaust does produce some black 'soot'. Not overwhelming but definitely present. ALSO, oil level doesn't seem to be affected but I've only put about 100 miles on it. No visible leaks.

In reply to # 1594420 by trtyme Maybe it is running VERY rich?

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TriumphFan Avatar
TriumphFan Silver Member Jim S
Cumming, GA, USA   USA
1967 Triumph GT6 MkI "Cantankerous"
Does the engine smoke? What color is the oil? If it turns black quickly you may have blow-by. You need to do a leak down test to be sure.



"If you didn't build it, it's not really yours"

LFMTR4 Avatar
LFMTR4 Lou Mijares
Scottsboro, AL, USA   USA
Yeah, I think that is rich running. If you are burning oil, you will see blue-grey smoke as it idles. Have the carbs been rebuilt? You might want to run some Seafoam through the tank to clean them and see if that helps but it looks like they are real rich. If you need to have them rebuilt, there is an expert on here that does that at a very attractive price - Poolboy. I'm sure he'll be along to help diagnose the plugs.



Edited 1 time(s). Last edit at 2019-02-05 08:28 AM by LFMTR4.

poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
Tanks, Lou.
Yeah, those plugs look like there's a lot of incomplete combustion going on...too rich, too much gas.
One side effect of that much excess gas is dilution of the motor oil, in effect washing down the cylinder walls...some of that oil and gas mix will coat the plugs,too.
Your compression numbers look fine, in fact GOOD, to me.
I think the problem is the carbs and the fact that they are 73 versions only add to that suspicion.



ZS carb repairs
kencorsaw@aol.com

BRAVOZULU9 Christian Ballester
Alexandria, VA, USA   USA
Thanks Ken! I sent you an email.



In reply to # 1594429 by poolboy Tanks, Lou.
Yeah, those plugs look like there's a lot of incomplete combustion going on...too rich, too much gas.
One side effect of that much excess gas is dilution of the motor oil, in effect washing down the cylinder walls...some of that oil and gas mix will coat the plugs,too.
Your compression numbers look fine, in fact GOOD, to me.
I think the problem is the carbs and the fact that they are 73 versions only add to that suspicion.

dsixnero Avatar
dsixnero Dan Colanero
Westville, NJ, USA   USA
Compression looks ok, black plugs is fuel, perhaps the incorrect timing was the cause or Strombergs can be tricky. Pull the valve cover and see if the guides were replaced, also hook up a vachume guage. Ask them what cam did they install? Dan

clifish Avatar
clifish Cliff Deger
St. James, NY, USA   USA
Christian you won't do better by having anyone but Ken rebuild the carbs, he did both of mine and the support he gave before and after is priceless.



74 TR6 - Carbs by POOLBOY
81 Corvette

tapkaJohnD Avatar
tapkaJohnD John Davies
Lancaster, Lancashire, UK   GBR
If you have been running the engine, but not on the road, before doing a plug check, it can be difficult to interpret.
Best is to take it out with a plug spanner to hand.
Give it an Italian tune-up, several miles of hard, foot down max revs. T
Then suddenly, cut the ignition and coast to a halt - you must choose the spot wisely.
And only then inspect the plugs that will still be VERY HOT, as they have just been working hard. (Gloves as well as the spanner!)

Apart from anything else it's another excuse to give your Triumph a run!

Having said that, I agree - those plugs look to be due to too rich a mixture, not oiled.
John

titanic Berry P
Albany, OR, USA   USA
I think that the first (and easiest) culprit to eliminate would be to check that the choke isn't partially "on" even when the choke knob is in. Also, remove the carb dampers and make sure that the air valves are rising and equal when the engine is accelerating. If the needles are binding in the jets or the diaphragms are torn, a very rich mixture is produced.
Berry

tirebiter Jeff Garber
Dighton, MA, USA   USA
In reply to # 1594419 by BRAVOZULU9 However, what I'm looking for are suggestions as to what ELSE may be causing this so that I can incrementally troubleshoot instead of going straight to removing the head.

Instead of going straight to removing the carbs, I suggest you check the following and let the forum know what you find :

1) Do what Berry p suggests, make sure the "choke" levers close all the way when the knob is pushed in

2) Poolboy alludes to the possibility of fuel in the crankcase. See if the oil level is above normal



In reply to # 1594419 by BRAVOZULU9 Initial Thoughts on My Part: Is is possible that somehow crankcase venting is not occurring properly?

I Agree fuel fouled. Dry and sooty, black exhaust smoke are all symptoms of a rich air/fuel mixture. I'd be interested in knowing what the timing was before you retarded it back to "normal". If the ignition timing was advanced enough, that amount of fuel could have been getting burned off and not fouling the spark plugs. Especially in light of "1500 - 1800 RPM" idle speed.

It seems to me as if the spark plugs could be the result of altering the ignition timing and making the vacuum unit inoperative. The spark plugs also indicate that each cylinder is exactly matched and both carbs are working the exact same way.



Edited 1 time(s). Last edit at 2019-02-05 01:28 PM by tirebiter.

BRAVOZULU9 Christian Ballester
Alexandria, VA, USA   USA
Gents,

Thanks so very much for all of the information and guidance - this is exactly what I was looking for! I'll keep everyone posted on how it proceeds once I get a chance to check these out!

I wish I could respond to everyone personally.

Best,

skootch13 Avatar
skootch13 Aaron K
Cincinnati, OH, USA   USA
What's type of plugs are they? Many here find the Champion's work the best. Myself included. Can't remember the number right now. Anyone?



1972 Sapphire Blue TR6

1959 (Registered '60) TR3 TS61635 L

Uberxy Avatar
Uberxy Steve Fox
Va, Charlottesville, USA   USA
Have a look at the diaphragms. You never know. I carry a spare in the glove box.



SR
73 TR6
86 930

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